Abstract

The unique properties of the noncommon-atom InAs/GaSb short-period-superlattices (SPSL) strongly depend on the interface structure. These interfaces are characterized using transmission electron microscopy(TEM). The compositional sharpness is obtained from the comparison of the experimental contrast in two-beam dark-field TEM images with simulated intensity profiles, which are calculated assuming that the element distribution profiles are described by sigmoidal functions. The interfacial intermixing, defined by the chemical width, is obtained for SPSL with different periods and layer thicknesses, even in the extreme case of nominally less than 3 ML thick InAs layers. Nominal 1 ML InSb layers intentionally inserted are also identified.

Received 30 October 2009Accepted 18 December 2009Published online 12 January 2010

Acknowledgments:

We acknowledge B. Jenichen for a careful reading of the manuscript and A. Pfeiffer for technical assistance. Part of this work has been sponsored by the European Commission (Project No. FP6-017383, DOMINO).